title: Deadpan contributes to the robustness of the notch response.
abstract: Notch signaling regulates many fundamental events including lateral inhibition and boundary formation to generate very reproducible patterns in developing tissues. Its targets include genes of the bHLH hairy and Enhancer of split [E(spl)] family, which contribute to many of these developmental decisions. One member of this family in Drosophila, deadpan (dpn), was originally found to have functions independent of Notch in promoting neural development. Employing genome-wide chromatin-immunoprecipitation we have identified several Notch responsive enhancers in dpn, demonstrating its direct regulation by Notch in a range of contexts including the Drosophila wing and eye. dpn expression largely overlaps that of several E(spl) genes and the combined knock-down leads to more severe phenotypes than either alone. In addition, Dpn contributes to the establishment of Cut expression at the wing dorsal-ventral (D/V) boundary; in its absence Cut expression is delayed. Furthermore, over-expression of Dpn inhibits expression from E(spl) gene enhancers, but not vice versa, suggesting that dpn contributes to a feed-back mechanism that limits E(spl) gene expression following Notch activation. Thus the combined actions of dpn and E(spl) appear to provide a mechanism that confers an initial rapid output from Notch activity which becomes self-limited via feedback between the targets.
authors.affiliation: Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom.
authors.forename: A Burcu
authors.initials: AB
authors.lastname: Babaoğlan
authors.forename: Ben E
authors.initials: BE
authors.lastname: Housden
authors.forename: Marc
authors.initials: M
authors.lastname: Furriols
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Bray
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics* / Q000378:metabolism*; D004268:DNA-Binding Proteins; D004330:Drosophila / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism*; D005123:Eye / Q000254:growth & development / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism*; D051880:Receptors, Notch / Q000235:genetics* / Q000378:metabolism*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014921:Wings, Animal / Q000254:growth & development / Q000378:metabolism
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D009687:Nuclear Proteins; D051880:Receptors, Notch; D012097:Repressor Proteins; D014157:Transcription Factors; C121960:E(spl)m7-HLH protein, Drosophila; C066381:ct protein, Drosophila; C078020:Dpn protein, Drosophila